Valve assembly



Dec. 18, 1962 R. H. CURRY VALVE ASSEMBLY Filed Nov. 5, 1959 INVENTOR.

RISDEN HALE CURRY FINN G. OLSEN ATTORNEY United States Patent 3,068,899 VALVE ASSEMBLY Risden Hale Curry, 219 W. Kingsley St., Ann Arbor, Mich. Filed Nov. 5, 1959, Ser. No. 851,116 9 Claims. (Cl. 137-623) The present invention relates to a control valve assembly adapted particularly but not exclusively for use with a hydraulically or pneumatically operated piston and cylinder assembly.

In the use of hydraulic or pneumatic cylinders, a fourway valve is normally employed for controlling their operation. A pressure control valve is positioned between the four-way valve and the cylinder for controlling the pressure of the fluid to the cylinder and thereby the rate of movement of the piston therein.

It is an object of the present invention to provide an improved control valve assembly which is constructed and arranged so that it will perform the dual functions of a three-way valve and a pressure control valve.

It is another object of the present invention to provide an improved control valve assembly of the foregoing character which is adapted for controlling automatically the operation of a hydraulic or pneumatic piston and cylinder assembly.

It is still another object of the present invention to provide an improved control valve assembly of the foregoing character which controls the speed of operation of a double acting piston and cylinder assembly by regulating the back pressure of the fluid acting against the piston from the exhaust side of the cylinder.

It is still another object of the present invention to provide an improved control valve assembly wherein the body thereof is formed as two elongated sections into which the valve chamber and passageways can be bored so as to provide a simplified low cost unit and one which allows a plurality of such valve assemblies to be part of a single structural unit.

It is still another object of the present invention to provide a plurality of control valve assemblies having a common body and which are constructed and arranged to facilitate rapid, low cost production.

It is still another object of the present invention to provide an improved control valve assembly adapted for use with a piston and cylinder assembly wherein said control valve assembly provides means for effecting slow or rapid traverse of the piston at desired time intervals during a stroke of the piston.

Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several Views.

In the drawings:

FIGURE 1 is a fragmentary front elevational view partly in section showing a plurality of control valve assemblies having a common body portion and showing schematically a piston and cylinder assembly and controls associated therewith for cooperating with some of said valve assemblies in the operation of the piston and cylinder assembly;

FIGURE 2 is an enlarged section taken on the line 2-2 in FIGURE 1;

FIGURE 3 is an enlarged section taken on the line 33 of FIGURE 2; and

FIGURE 4 is an enlarged section taken on the line 4-4 of FIGURE 2.

Referring now to the drawing, the invention will be described in greater detail. As shown in FIGURE 1, several control valve assemblies may be part of a unitary structure and only one such valve assembly 10 p way 46 together with transverse passageway 48.

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will be described in detail, and common reference numbers in the several assemblies 10- will indicate similar parts. The several valve assembles 10 have an integral valve body 12 formed from two sections 14 and 16, FIGURE 2, the purpose of which is to facilitate low cost production using standardized parts.

The front section 14 has a plurality of bores therein defining valve chambers 18. Positioned in the upper region of each chamber 18 is a liner 26 which has a radially inwardly extending collar 22 containing therein exhaust ports or radial passageways 24, and on the radially outer ends of said passageways 24 is a circumferential groove 26 into which said passageways 24 open. On the radially inner side of said collar 22, above the inner ends of said passageways 24, is a circumferential groove containing an 0 ring 28.

Located below the liner 20 is a metallic ring 3% which has a plurality of outlet ports or radial passageways 32 opening into an outer circumferential groove 34, and

positioned between the liner 2! and the ring 38 are rubber sealing rings 36 and 38. As will be described, the radial passageways 24 and their associated groove 26 provide communication between the chamber 18 and the longitudinal exhaust passageway 40 via the transverse passageway 42. Similarly, the radial passageways 32 and their associated groove 34 provide communication between the chamber 18 and the outlet passageway 44 and conduit 45.

The sections 14 and 16 provide two other passageways communicating with the chamber 18. The first of these is the high pressure longitudinally extending inlet passage- The second of these is the relatively small pilot valve controlled passageway 50 which opens into the upper regions of the chamber 20 and extends to the inlet passageway 46.

A bleeder outlet port 52 also provides communication with the atmosphere for a purpose to be explained.

Positioned within the chamber 18 is a floating piston or a valve member 54 which carries an O ring in its upper periphery providing a seal with the liner 20. The valve member then has a reduced mid portion which passes through the collar 22 and a second seal is provided by the 0 ring 28. The valve member 5 4 has a still further reduced lower end portion which projects in spaced relation through the ring 30.

In the bottom of chamber 18 is a coil spring 56 which supports and urges upwardly the ball or valve element 58. In its upper position, as seen in the middle valve assembly of FIGURE 1, the valve element 58 will be seated on the rubber sealing ring 60 on the underside of ring 3%, thereby providing a seal between the portion of chamber 18 therebelow into which the transverse inlet passageway opens and the upper regions of chamber 18 with which the exhaust passageway 40 and the outlet passageway 44 com- However, when the valve member 54 is depressed or lowered to the position shown in FIGURE 2, the reduced end thereof will depress the valve element 58 allowing communication between inlet passageway 46 and outlet passageway 44 via the interior. of chamber 18. At the same time the mid portion of valve member 54 will have interrupted communication between the exhaust passageway 40 and the interior of chamber 18 by closing pressure can flow through passageways 46 and 48 into the interior of valve chamber 18 and out through outlet ports 32 to the outlet passageway 44 and conduit 45.

' When the valve assembly is in the position shown by the middle unit in FIGURE 1 with the valve member 54 raised and the ball 58 seated in its closed position, fluid can then flow from the conduit 45 and passageway 44 back through the valve chamber 18 and out the ports 24 to the exhaust passageway 40. For the purpose of controlling the rate of return flow through the valve chamber 18, an adjustable stop member 60 which forms a part of the control unit 62 (to be described) projects into the chamber 18 so as to limit the extent to which the valve member 54 can be raised. This has the effect of controlling the amount the exhaust ports 24 are opened during return flow of fluid through the chamber 18. Thus, varying the setting of the stop member 60 will have the effect of varying the rate of return flow of the fluid through chamber 18.

For the purpose of controlling the time of movement of the valve member 54, a pilot valve 64, FIGURE 2, is located in the passageway 50 and is operated by an electrical solenoid 66. By this means the valve 64 can be lowered from the position shown in FIGURE 2 to a position closing passageway 50 and thereby preventing pressurized fluid from passageway 46 from acting on the upper surface of valve member 54. Under these circumstances there will be no effective pressure acting downwardly on valve member 54 and the spring 56 will urge ball or valve element 58 and the valve member 54 upwardly. Return flow of fluid from conduit 45 will then act on the under surface of valve member 54 urging it to the position shown in the center of FIGURE 1. Thereafter, when it is desired to reverse flow again through valve assembly 10, the solenoid 66 actuates valve 64 opening passageway 50 allowing high pressure fluid to act on the upper surface of valve member 54 depressing it and valve element 58 so that fluid can again flow from the passageway 46 through the valve chamber 18 to the conduit 45.

One of the principal applications that can be made of the present invention is for controlling the operation of a hydraulic or pneumatic piston and cylinder assembly. For the purpose of describing this operation reference is made to FIGURE 1 wherein a schematic showing is made of a piston 68 in the cylinder 70. Conduits 45 from the left and center valve assemblies are connected to opposite ends of cylinder 70. A rod 72 is connected to the piston 68 and has a limit stop member 74 adapted to actuate the limit switches 76 and 78. The latter switches can be in any conventional electrical circuit including conductors 80 which are connected to solenoids 66.

The operation of this arrangement will now be explained. Assume that fluid under pressure is entering the cylinder 70 forcing the piston 68 and its rod 72 to the right. Such fluid will be supplied under pressure from passageway 46 through passageway 48, chamber 18, outlet ports 32, passageway 44 and conduit 45 to the left end of cylinder 70. As the piston 68 moves to the right, fluid on the right side of the piston will be discharged through the conduit 45 at the right end of the cylinder 70 and through the center valve assembly 10 to the exhaust passageway 40. When the limit stop member 74 actuates switch 78, this cycle will be reversed and the component parts of the center valve assembly 10 will assume the arrangement of the left valve assembly 10 and vice versa. Then the fluid will enter the cylinder 70 at the right end and will discharge from the left end.

When it is desired to change the rate of travel of the piston 68, this can be accomplished merely by changing the settings of the stop members 60 so as to vary the effective sizes of the exhaust ports 24, as was previously described, and thereby vary the effective back pressure on the piston 68. Since the rate of travel of the piston 68 is a direct function of the total pressures acting on opposite sides thereof, such variation of the back pressure will directly control the rate of travel of the piston 68.

The control unit 62 is also constructed and arranged so as to permit a two speed operation of the piston 68. Thus, if a slow and rapid traverse in a single stroke of the piston 68 is desired, this can be accomplished by the use of control unit 62. The latter includes the pin 80 which is threadedly connected to the stop member 60 and is axially movable in the cylindrical member 82. The latter has its upper half externally threaded for connection to the cap 84. The lower portion of the cylindrical member 82 has a shoulder 86 for seating in the cap 84, and a jam nut 83 fits on the upper portion of the cylindrical member 82 for locking the same in place. The cap 82 is secured on the top of the valve body 12 by a plurality of screws 90.

The pin 80 has a pair of jam nuts 92 for limiting the extent that the stop member 60.is permitted to enter the valve chamber 18. A thin piston 94 is threadedly connected to the pin 80 and limits the extent that the stop member 60 can be withdrawn from the valve chamber 18. Thus, at the two ends of travel of the stop member 68', two different settings for openings of the valve ports 24 are provided. When the stop member 60 is in its uppermost position, rapid traverse of the piston 68 is permitted, and when in its lowermost position a slower traverse is permitted.

The stop element 60 is adapted to be held in its lowermost position by air pressure acting downwardly on the piston 94. Air under pressure for this purpose can be supplied through the conduit 96 from any suitable source, such as the high pressure inlet passageway 46. If desired, a coil spring 98 may be used to urge the stop member 60 to its uppermost position. Also, suitable 0 ring seals, as shown in the drawing, may be used to provide fluid tight joints between the various parts of control unit 62.

Thus, it can be seen that by use of a suitable limit switch (not shown) of the type shown at 76 and 78, a solenoid valve controlled thereby can act to introduce high pressure air against the piston 94 to depress the same, and thereby restricting the size of valve ports 24 at any time in the stroke of piston 68. Similarly, a switch (not shown) may be used to release pressure on piston 94, thereby allowing stop member 60 to be raised and again allowing rapid traverse of piston 68. Also, the two effective settings of the stop member 60 can be selectively varied by the threaded settings of the pin relative to the jam nuts 92 and the piston 94.

In order to provide a unitary control system for several piston and cylinder assemblies, a series of valve assemblies 10 can be made a part of the single valve body 12, as shown in FIGURE 1. This permits use of standard parts throughout and the passageways therein can be formed by simple, low cost production operations. Suitable seals, such as 0 rings can be used at all connecting parts or passageways.

Having thus described my invention, I claim:

1. A control valve assembly comprising a body defining a valve chamber with a high pressure fluid inlet port, a high pressure fluid outlet port and an exhaust port, a valve element positioned in said chamber for normally closing communication between said inlet port and said outlet and exhaust ports, a valve member movable relative to said valve element and having a first position in said chamber for displacing said valve element from its normal position to a position allowing fluid communication between said inlet and outlet ports and for closing communication with said exhaust port, said valve member having a second position in said chamber in which said valve element can return to its normal position and in which said exhaust port will be opened a predetermined amount, means for selectively changing the second position of said valve member for varying the opening of said exhaust port, said valve member having first and second opposite fluid pressure responsive surfaces for effecting movement of said valve member to either its first position or its second position, one of said pressure responsive surfaces having a greater effective surface area than the other surface for moving said valve member to said first position, said other surface being continuously exposed to fluid pressure adjacent said outlet port, and means for intermittently admitting high pressure fluid into said chamber adjacent said one surface for effecting movement of said valve member to said first position.

2. A control valve assembly comprising a body defining a valve chamber with a central axis and with a high pressure fluid inlet port, a high pressure fluid outlet port and an exhaust port opening laterally therefrom and positioned in axially spaced relation, a valve element spring biased in an axial direction to a normally seated position across said valve chamber closing communication between said inlet port and said outlet and exhaust ports, an axially movable valve member having a first position in said valve chamber for displacing said valve element from its spring biased normally seated position to a position allowing fluid communication between said inlet and outlet ports and for closing said exhaust port, said valve member having a second position in said valve chamber in which said valve element can return to its normally seated position and in which said exhaust port will be uncovered a predetermined amount to allow a restricted communication between said outlet port and said exhaust port, means for selectively changing the second position of said valve member for varying the extent to which said exhaust port is uncovered, said valve member having first and second opposite fluid pressure responsive surfaces for effecting movement of said valve member to either its first position or its second position, one of said pressure responsive surfaces having a greater effective surface area than the other surface for moving said valve member to said first position, said other surface being continuously exposed to fluid pressure ad jacent said outlet port, and means for intermittently admitting high pressure fluid into said chamber adjacent said one surface for effecting movement of said valve member to said first position.

3. A control valve assembly comprising a body defining a valve chamber with a central axis and with a high pressure fluid inlet port, a high pressure fluid outlet port and an exhaust portopening laterally therefrom and positioned in axially spaced relation, a valve element spring biased in an axial direction to a normally seated position across said Valve chamber closing communication between said inlet port and said outlet and exhaust ports, an axially movable valve member responsive to high pressure fluid for movement to a first position in said valve chamber of displacing said valve element from its spring biased normally seated positionto a position allowing fluid communication between said inlet and outlet ports and for closing said exhaust port, said valve member having a second position in said valve chamber in which said valve element can return to its normally seated position and in which said exhaust port will be uncovered a predetermined amount to allow a restricted communication between said outlet port and said exhaust port, said valve member being responsive to fluid under pressure at said outlet port for moving'said valve memher to said second position, control means for effecting introduction of high pressure fluid into said valve chamber for moving said valve member against the fluid pressure at said outlet port to its first position, and means for selectively changing the second position of said valve member to vary the extent to which said exhaust port is uncovered.

4. A control valve assembly comprising a body defining a valve chamber with a high pressure fluid inlet port, a high pressure fluid outlet port and an exhaust port, a valve element positioned in said chamber for normally closing communication between said inlet port and said outlet and exhaust ports, spring means for urging said valve element to its normal position, a movable valve member in said chamber having a first position fordisplacing said valve element from its normal position to a position allowing fluid communication between said inlet and outlet ports and for closing communication between said exhaust port and the inlet and outlet ports, said valve member having a second position in said chamber in which said valve element can be returned by said spring means to its normal position and in which said exhaust port will be opened a predetermined amount to allow a predetermined fluid communication between said outlet port and said exhaust port, said valve member being responsive to fluid under pressure at said outlet port for moving said valve member to said second position, said body also having a pilot valve port opening into said chamber for supplying fluid under pressure and located so that such fluid will act on said valve member to move the same in opposition to the fluid under pressure at said outlet port to said first position, pilot valve means for introducing fluid under pressure at desired time intervals through said pilot valve port, and means for selectively changing the second position of said valve member so as to vary the effective communication that can occur between said outlet port and said exhaust port.

5. A control valve assembly as claimed in claim 4 wherein said valve member has a larger area responsive to fluid under pressure from said pilot valve port than is responsive to fluid under pressure at said exhaust port, and wherein said pilot valve port is in communication with the same source of fluid under pressure that communicates with said inlet port.

6. A control valve assembly comprising a body having two longitudinal sections secured together in side-by-side relation, one of said sections defining a plurality of valve chambers each having a high pressure fluid inlet port, a high pressure fluid outlet port and an exhaust port, said one section having a plurality of passageways extending respectively from the inlet ports of said valve chambers to the abutting surface of the other section, each chamber containing therein a valve element normally positioned for closing communication between said inlet port and said outlet and exhaust ports, and each chamber containing a movable valve member having a first position for displacing the valve element therein from the normal position thereof to a position allowing fluid communication between the inlet and outlet ports thereof and for closing communication with the exhaust port thereof, each valve member being movable to a second position in its chamber in which its associated valve element can return to the normal position thereof and in which said exhaust port will be opened a predetermined amount, the other of said sections including a longitudinally extending high pressure fluid passageway with a plurality of passageways extending toward said one section and communicating respectively with said passageways in said one section, said sections also defining a plurality of pilot valve passageways communicating between said high pressure fluid passageway and said chambers for use in moving the valve members to said first position, and a plurality of pilot valves extending into said pilot valve passageways for selectively opening and closing each of such passageways.

7. A control valve assembly as defined in claim 6 wherein means are provided for selectively changing the second position to which each valve member can be moved so as to change the amount that the associated exhaust port can be opened.

8. A control valve assembly as defined in claim 6 wherein said other section includes a longitudinally extending exhaust passageway, and said sections have aligned passageways communicating respectively between the exhaust ports of said chambers and said exhaust passageway.

9. A control valve assembly as defined in claim 6 wherein said pilot Valves are operated by electrical solenoids mounted on said body.

(References on following page) 7 8 References Cited in the file of this patent 2,587,357 McPherson Feb. 26, 1952 2,609,794 Towler Sept. 9, 1952 UNITFED STATES PATENTS 2,625,844 Beckett et a1 J an. 20, 1953 458,191 Rlpley 9 25,1891 2,691,964 Stickney Oct. 19, 1954 986,410 Sherman ar. 7, 911 5 2,478,002 Mott Aug. 2, 1949 FOREIGN PATENTS 909,099 France Nov. 26, 1945 

